Philanthropy’s quest to improve K-12 education feels stuck in a rut. Some of the biggest funders on the scene remain devoted to a reform strategy that so far has failed to yield transformative change, while a range of other funder-backed efforts aren’t yet operating at a scale likely to produce major breakthroughs.“There’s no dramatic change,” Bill Gates told New York Times columnist Nicholas Kristof last year, summing up the results of his own foundation’s efforts, which have entailed spending billions of dollars over 15 years.